1. Field of the Invention
The present invention relates generally to medical devices and methods. More particularly, it relates to devices and methods for the delivery of substances to breast milk ducts.
2. Background of the Invention
The current state of the ductal access art is that the ducts in a breast are accessed one-by-one with a catheter. The human breast has from 6–12 ducts. This process of duct-by-duct access has many disadvantages, including that the process is slow and that it is very difficult after finishing lavage of one duct to know which of the other ducts of a breast have or have not been lavaged. Thus, under the one-duct-at-a-time duct lavaging or accessing system it is easy to miss a duct or access or duct twice. The present invention at least partly overcomes these deficiencies.
U.S. Pat. No. 5,763,415 to Sukumar claims a method of treating the ductal epithelium of a mammary glad prophylactically for cancer by ductal cannulation and administration of a vector comprising thymidine kinase into the duct. The delivery of epithelium-destroying agents to breasts by ductal cannulation is described in WO 97/05898.
Various methods and techniques of duct-by-duct access have been described, including methods described in Love and Barsky, (1966) Lancet 348: 997–999, and Presentations about ductal access made in Love, (1992) “Breast duct endoscopy: a pilot study of potential technique for evaluating intraductal disease,” presented at 15th Annual San Antonio Breast Cancer Symposium, San Antonio, Tex., Abstract 197; Barsky and Love (1996) “Pathological analysis of breast duct endoscoped mastectomies,” Laboratory Investigation, Modern Pathology, Abstract 67; and Lewis (1997) Biophotonics International, pages 27–28, May/June 1997.
A company called Diagnostics. Inc. formed in 1968, produced devices to obtain breast ductal fluid for cytological evaluation. The devices included a breast duct catheter to infuse fluid into and collect fluid from individual ducts. The devices were sold prior to May 28, 1976 for the purpose of collecting breast ductal fluid for cytological evaluation.
A patent application entitled “Methods and kits for obtaining fluid and cellular material from breast ducts,” U.S. Ser. No. 09/067,661 filed Apr. 28, 1998, and its continuation-in-part, U.S. Ser. No. 09/301,058 filed Apr. 28, 1999, describe and claim infusing a small amount of fluid into the duct and collecting the fluid using a catheter. Related applications include U.S. Ser. Nos. 60/143,476 and 60/143,359, both filed Jul. 12, 1999, 60/134,613, filed May 18, 1999, and-60/114,048 filed Dec. 28. 1998, all of which are herein incorporated by reference in their entirety. Provisional application No. 60/170,997, filed Dec. 14, 1999, and non-provisional application 09/473,510, filed Dec. 28, 1999 describe methods and apparatus for delivering a substance to a breast duct.